1. Field of the Invention
This disclosure relates to network communications, packets, data units, and the transmission of and receipt of network traffic.
2. Description of the Related Art
Networks such as the Internet carry a variety of data communicated using a variety of network devices including servers, routers, hubs, switches, and other devices. Before placing a network into use, the network and the network devices, network media, network segments and network applications included therein, may be tested to ensure successful operation. Network media, segments, devices and applications may be tested, for example, to ensure that they function as intended, comply with supported protocols, and can withstand anticipated traffic demands. Such testing may also be performed on already deployed network devices, network segments and network applications.
To assist with the construction, installation and maintenance of networks, network segments, network applications and network devices, networks may be augmented with network analyzing devices, network conformance systems, network monitoring devices, and network traffic generators, all of which are referred to herein as network testing systems. The network testing systems may allow for analyzing the performance of networks, network applications and network devices by capturing, modifying, analyzing and/or sending network communications.
Network testing systems may send and receive a large amount of network traffic and may establish and end many communication sessions. Network interface devices, units, cards, chips and the like within a network testing system may perform much of the work in sending and receiving network traffic and establishing and ending sessions. To track network communications sent and received by network testing systems so that network devices may be tested, network communications are prepared with test information. The functioning of a device under test may be evaluated based on review of the test information included in network communications.
A thorough test of a complex network or a network device may involve the transmission, reception, and evaluation of literally millions of packets of network traffic. Since test data may be measured on each received packet, the sheer volume of test data may preclude real-time or near-real-time analysis of the results of the test. Conventional test systems may transfer all of the test statistics to a common processor for analysis. However, the rate at which test statistics are accumulated may be much faster than the rate at which the test statistics can be communicated to the analysis processor. In this case, the analysis processor may not receive all of the test statistics until the testing has been completed. Thus the test results may be determined only after the fact by post analysis of the test data.
Throughout this description, elements appearing in figures are assigned three-digit reference designators, where the most significant digit is the figure number and the two least significant digits are specific to the element. An element that is not described in conjunction with a figure may be presumed to have the same characteristics and function as a previously-described element having a reference designator with the same least significant digits. In cases where a plurality of elements perform the same general function, the elements may be given a common reference designator number with a letter suffice.